Rotary connector with valve

ABSTRACT

A rotary connector with valve, comprising first and second connector members ( 1, 2 ) having connector terminal parts ( 5, 6 ) and fitting parts ( 7, 8 ) with hollows ( 3, 4 ) as fluid passages formed therein and a valve member ( 12 ), wherein the first and second connector members are rotatably connected to each other by fitting the fitting parts thereof to each other and the valve member is stored in a valve storage part ( 11 ) formed in the fitting part, valve pressing parts ( 14, 15 ) are provided on the first and second connectors ( 1, 2 ) on the side of the valve storage part, and at least a part of the valve member is pressingly held between the both valve pressing parts to hold a sealability, and a frictional force acting between the both valve pressing parts and the valve member is set so as to come within such a range that the first and second connector members can be rotated each other, whereby a structure allowing an easy assembly and an absorption of the twist of a line can be provided.

TECHNICAL FIELD

[0001] The present invention relates mainly to connectors used ininfusion lines, and more particularly to valved rotary connectors thatare provided with a one-way valve or the like that is used in order toprevent backflow.

BACKGROUND ART

[0002] For conventional valved connectors, there are those of themale/female type and the tube-bonded type. In the male/female type, amain body having a valve-seating portion in which a valve is disposed isprovided with a male or a female connector portion. The tubes to beconnected are provided with corresponding female or male connectors, andconnection is established by coupling the male and female connectorportions together. It is possible to employ various structures forcoupling the two, and ordinarily it is necessary that the two can berotated relatively to one another, as in a screw-type connection. Withsuch a male/female connector, the member to be connected can be attachedor detached as necessary. In the case of the tube-bonded type, a tube isdirectly bonded to a tube-shaped linking portion provided on a memberfor seating a valve, thereby coupling them together. Consequently, thecoupling is permanent.

[0003] When using such a conventional valved connector, relativerotation is impossible at the coupling portion between connector andtube in a state in which the tube line is connected by the connector.Consequently, when the tube is twisted, the rotational torque acts onthe tube, whereby obstruction of the flow path in the tube or damage tothe tube may be caused.

[0004] Moreover, in the case of a male/female connector, when the tubeis twisted in a state in which the tube line is connected, the screwingof the screw-joint portion may be loosened, and in some cases it evenmay be dislodged.

[0005] Furthermore, in the case of twisting the tube-bonded connectors,there is no loosening or dislodging of the connection, but it cannot beavoided that the flow path in the tube is obstructed or that the tube isdamaged. Furthermore, in tube-bonded connectors there is the problemthat it is not possible to rearrange the line, and that the setup isbothersome.

DISCLOSURE OF THE INVENTION

[0006] It is an object of the present invention to present a valvedconnector that can be assembled easily, with which reassembly of theline is possible, so that it is easy to alter or adjust the direction ofan infusion port or a branching means such as a three-way stopcockprovided in a line, and with which twisting of the line can be absorbed,so that the possibility of loosening or disconnection as well as theload on the tube can be reduced.

[0007] A rotary connector with valve according to a basic configurationof the present invention includes a first and a second connector membereach having a fitting portion and a connector portion provided with aninner bore serving as a liquid flow path, and a valve member arranged inthe liquid flow path. The first and the second connector member arecoupled rotatably to one another by fitting the fitting portionstogether, and the valve member is seated in a valve-seating portionformed in the fitting portions. The fitting portions of the first andthe second connector members are provided with respective valve-pressingportions facing the valve-seating portion, and, by clamping and pressingat least a portion of the valve member between the two valve-pressingportions, liquid-tightness is preserved between the inner bore and theoutside of the connector at a location at which the two fitting portionsare coupled. Moreover, a pressing force with which the twovalve-pressing portions act on the valve member is set such that africtional force exerted between the two valve-pressing portions and thevalve member is in a range that allows the first connector member andthe second connector member to rotate relatively to one another.

[0008] With this configuration, the first connector member and thesecond connector member can be rotated relatively to one another whilepreserving liquid-tightness, so as to absorb twisting of the tube aswell as the rotational torque acting on the tube and the object to beconnected.

[0009] In this configuration, it is preferable that at least one of theconnector portions of the first and second connector members has astructure with which objects to be connected can be engaged by mutualrotation. Moreover, the pressing force acting on the valve member is setsuch that the torque for rotating the first connector member and thesecond connector member relatively to one another against the frictionalforce exerted between the two valve-pressing portions and the valvemember is smaller than the torque necessary to dislodge the engagementof the objects to be connected and the connector portion. Thus, theeffect of absorbing the twisting of the tube can be ensured withoutloosening the engagement between the connector portion and the objectsto be connected.

[0010] In the above configuration, it is preferable that the valvemember has a base portion that is substantially cylindrical and insideof which a valve is formed, and a flange formed at one end thereof Thevalve-seating portion is formed in one of the fitting portions, and hasa substantially circular cavity that is coaxial with the inner bore anda large diameter portion that is provided at an aperture end of thecavity, and an end face that is formed by a step between the largediameter portion and the cavity and that is perpendicular to the innerbore, which acts as one of the valve-pressing portions. An end face ofthe fitting portion that is not provided with the valve-seating portionacts as the other valve-pressing portion. The flange is clamped andpressed between the two valve-pressing portions. With thisconfiguration, the effect of the present invention can be attained in aform that is suitable to the structure of connectors.

[0011] In the above configuration, it is preferable that the fittingportion that is not provided with the valve-seating portion has avalve-holding portion that protrudes in an axial direction towards thevalve-seating portion on an inner peripheral side of the end faceforming the valve-pressing portion, and protrusion of the valve membertoward the inner bore is prevented by the valve-holding portion. That isto say, when the flange is clamped by the valve-pressing surfaces, theconnector members rotatively slide with respect to the valve member, andthus there is the risk that a force acts on the flange in the directioncausing the valve member to slip from between the valve-pressingsurfaces into the inner bore, but with this configuration such slippingcan be prevented.

[0012] In the above basic configuration of the present invention, it ispreferable that the valve member has a base portion that issubstantially cylindrical and inside of which a valve is formed. Thevalve-seating portion is formed in one fitting portion, and has asubstantially circular cavity that is coaxial with the inner bore, aninner peripheral surface at an end portion thereof acting as avalve-pressing portion. The fitting portion that is not provided withthe valve-seating portion has a cylindrical protrusion portion that islinked to the inner bore, an outer peripheral surface of the cylindricalprotrusion acting as a valve-pressing portion. A cylindrical end portionof the base portion of the valve member is clamped and pressed betweenthe two valve-pressing portions. With this configuration, the effect ofthe present invention can be attained in a form that is suitable to thestructure of connectors.

[0013] In the above configuration, it is preferable that both of the twovalve-pressing portions have a ring-shaped rib, and the ring-shaped ribsare arranged in opposition to one another, such that they abut againstthe valve member. With this configuration, liquid-tightness can bepreserved reliably, and both thread portions can be rotated with a smalltorque.

[0014] It is preferable that dimensions of the ribs are set such that anamount of the valve member deformed by pressure is in a range of 10 to70% of the valve member's wall thickness. It is further preferable thatthis range is 30 to 60%.

[0015] In the above configurations, the valve member seated in thevalve-seating portion may be a one-way valve member.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 is a sectional view showing a connector with one-way valveaccording to Embodiment 1 of the present invention.

[0017]FIG. 2A is a sectional view showing a second connector member ofthe connector with one-way valve in FIG. 1.

[0018]FIG. 2B is a sectional view showing a first connector member ofthe connector with one-way valve in FIG. 1.

[0019]FIG. 2C is a sectional view showing a one-way valve memberconstituting the connector with one-way valve in FIG. 1.

[0020]FIG. 3 is a sectional view showing a connector with one-way valveaccording to Embodiment 2 of the present invention.

[0021]FIG. 4 is a sectional view showing a first connector member in theconnector with one-way valve in FIG. 3.

BEST MODE FOR CARRYING OUT THE INVENTION

[0022] Embodiment 1

[0023]FIG. 1 is a sectional view showing a connector with valveaccording to Embodiment 1. This connector is made of a first connectormember 1 and a second connector member 2. The first connector member 1and the second connector member 2 both have an inner bore 3, 4 servingas the flow path for a liquid. A male thread 5 serving as a connectorportion is formed on the outer surface of the first connector member 1,and a female thread 6 serving as a connector portion is formed on theinner surface of the second connector member 2.

[0024] The inner bore 3 of the first connector member 1 at the endhaving the male thread 5 is formed in a tapered shape, so that aluer-type end portion can be inserted and fitted. Also the inner bore 4formed at an inner tube portion 2 a of the second connector member 2 isformed in a tapered shape.

[0025] The first connector member 1 has an outer fitting portion 7 (asshown clearly in FIG. 2B, which is explained below). The secondconnector member 2 has an inner fitting portion 8 whose outer diameteris smaller than the inner diameter of the outer fitting portion 7.Consequently, the first connector member 1 and the second connectormember 2 can be coupled by inserting the inner fitting portion 8 intothe outer fitting portion 7 and fitting the two together. The outerfitting portion 7 and the inner fitting portion 8 have a step portion 9,10, and by engaging these step portions 9 and 10, the first connectormember 1 and the second connector member 2 are interlocked such thatthey are not inadvertently dislodged. The inner diameter of the outerfitting portion 7, the outer diameter of the inner fitting portion 8,and the positions of the step portions 9 and 10 are set such that thefirst connector member 1 and the second connector member 2 can berotated relatively to one another around the axis of the male thread 5and the female thread 6.

[0026] A valve-seating portion 11 is formed inside the inner fittingportion 8 of the second connector member 2. In this embodiment, aone-way valve member 12 is seated in the valve-seating portion 11.

[0027] The first connector member 1 and the second connector member 2can be made of a plastic material, and are preferably made using atransparent plastic material. The one-way valve member 12 is made of anelastomer with little elution, excellent abrasion resistance and lowcompressive permanent set, such as silicone rubber.

[0028]FIG. 2 shows sectional views in which the connector of FIG. 1 hasbeen taken apart. FIG. 2A shows the second connector member 2, FIG. 2Bshows the first connector member 1, and FIG. 2C shows the one-way valvemember 12. As shown in FIG. 2A, the valve-seating portion 11 includes acircular cavity, and has a large diameter portion 13 on its apertureend. L1 denotes the length of the large diameter portion 13 in the axialdirection. A ring-shaped rib 14 a is formed at a valve-pressing surface14 that is formed by a step between the large diameter portion 13 andthe circular cavity.

[0029] The inner end surface of the outer fitting portion 7 of the firstconnector member 1 shown in FIG. 2B constitutes a valve-pressing surface15, which opposes the valve-pressing surface 14. Also the valve-pressingsurface 15 is provided with a ring-shaped rib 15 a, similar to the rib14 a. The rib 14 a and the rib 15 a are arranged such that they are inopposition to one another when the first connector member 1 and thesecond connector member 2 are coupled. A substantially cylindricalvalve-holding portion la is formed on the inner side of the outerfitting portion 7.

[0030] As shown in FIG. 2C, the one-way valve member 12 has asubstantially cylindrical base portion 16, and a one-way valve 17 isformed inside of it. At one end, a flange 18 is formed. L2 denotes thelength of the flange 18 in the axial direction, d denotes the innerdiameter of the flange 18, and D denotes its outer diameter. The lengthand the outer diameter of the base portion 16, and the outer diameter Dof the flange 18, should be dimensioned such that the one-way valve 12fits into the valve-seating portion 11.

[0031] In the state in which the connector is assembled as shown in FIG.1, the valve-pressing surface 14 at the large diameter portion 13 of thesecond connector member 2 and the valve-pressing surface 15 at the firstconnector member 1 clamp the flange 18 of the one-way valve member 12,and the flange 18 is pressed from both sides. In this situation, theflange 18 of the one-way valve member 12 is deformed by the opposingribs 14 a and 15 a. Thus, an adequate pressing force is produced betweenthe ribs 14 a, 15 a and the one-way valve member 12. Consequently, theconnection portion of the inner bores 3 and 4 serving as the flow pathfor the liquid is sealed, and a liquid-tight portion functioning toprevent leaks is formed. Thus, not only is liquid-tightness preserved,but the pressure force is adjusted by suitably setting the dimensions ofeach member, and the friction force acting between the valve-pressingsurfaces 14, 15 and the one-way valve member 12 is restricted to a rangein which the first connector member 1 and the second connector member 2can be rotated relatively to one another. More specifically, it is setsuch that the first connector member 1 and the second connector member 2can be rotated relatively to one another with a torque that is smallerthan the torque that is necessary to unscrew the member that isscrew-jointed with the male thread 5 or the female thread 6.

[0032] It should be noted that when the flange 18 is clamped by thevalve-pressing surfaces 14 and 15, there is the risk that whenrotatively sliding the connector member relatively to the one-way valvemember 12, a force is applied to the flange 18 from between thevalve-pressing surfaces 14 and 15 in the direction in which the flange18 slips (slides) into the inner bore. The valve-holding portion la hasthe function to counter this force and to hold the flange 18 between thevalve-pressing surfaces 14 and 15.

[0033] Due to this action of the valve-pressing surfaces 14 and 15, thefirst connector member 1 and the second connector member 2 can berotated relatively to one another while maintaining liquid-tightness, sothat twisting of the tube or rotational torques acting on the tube orthe connected object can be absorbed without loosening the screwing ofthe male thread and the female thread.

[0034] It should be noted that it is not essential to provide the ribs14 a and 14 b, and it is also possible to employ a structure in whichthe valve-pressing surfaces 14 and 15 are pressed directly to the flange18. However, providing the ribs 14 a and 15 a ensures liquid-tightoperation and makes it possible to rotate both threaded portions withlittle torque.

[0035] The dimensions of the ribs 14 a and 15 a should be set such thata deformed amount of the flange 18 of the one-way valve member 12 is inthe range of 10 to 70% of the thickness of the valve wall. Morepreferably, it is 30 to 60%. Consequently, in the range in which thiscondition is satisfied, the spacing between the rib 14 a and the rib 15a should be smaller than the length L2 in the axial direction of theflange 18 of the one-way valve member 12. Therefore, the play forfitting the outer fitting portion 7 to the inner fitting portion 8 andthe length L1 of the large diameter portion 13 of the valve-seatingportion 11 should be set appropriately.

[0036] Embodiment 2

[0037]FIG. 3 is a sectional view showing a connector with valveaccording to Embodiment 2 of the present invention. This embodimentdiffers from Embodiment 1 in the configuration with which the flange 18of the one-way valve member 12 is pressed. The inner bore 3 of the firstconnector member 1 has a small diameter at the outer fitting portion 7,and is provided with a cylindrical protrusion 19. The outer peripheralsurface of the cylindrical protrusion 19 constitutes an innervalve-pressing surface 20. The inner peripheral surface of the largediameter portion 13 of the valve-seating portion 11 constitutes an outervalve-pressing surface 21. The valve-pressing surface 20 and thevalve-pressing surface 21 are in opposition, and the flange 18 of theone-way valve member 12 is clamped in the ring-shaped space formedbetween them. The valve-pressing surfaces 20 and 21 are provided withring-shaped ribs. 20 a and 21 a, respectively. It is preferable that thewall thickness (D−d)/2 of the flange 18 of the one-way valve member 12is formed slightly larger than the spacing between the opposingring-shaped ribs.

[0038] With this configuration, pressure is exerted on the innerperipheral surface and the outer peripheral surface of the flange 18from the valve-pressing surface 20 and the valve-pressing surface 21,respectively. Moreover, a portion of the flange 18 of the one-way valvemember 12 is deformed in the radial direction by the ring-shaped ribs 20a and 21 a provided on the valve-pressing surfaces 20 and 21, similar tothe effect of the ribs 14 a and 16 a in Embodiment 1, thus ensuring theeffect of the valve-pressing surfaces for preserving liquid-tightness.However, the ring-shaped ribs are not required, and it is also possibleto attain liquid-tightness when a structure without ribs is used.

[0039] The pressure force from the valve-pressing surfaces 20 and 21 isset such that the frictional force acting between the valve-pressingsurfaces 20 and 21 and the one-way valve member 12 is restricted to arange in which the first connector member 1 and the second connectormember 2 can rotate relatively to one another. More specifically, as inEmbodiment 1, it is set such that the first connector member 1 and thesecond connector member 2 can be rotated relatively to one another witha torque that is smaller than the torque that is necessary to unscrewthe member that is linked by the male thread 5 or the female thread 6.

[0040] Due to this effect of the valve-pressing surfaces 20 and 21, thefirst connector member 1 and the second connector member 2 can berotated relatively to one another while maintaining liquid-tightness, sothat twisting of the tube or rotational torques acting on the tube andthe connected object can be absorbed without loosening the screwing ofthe male thread and the female thread.

[0041] It should be noted that this embodiment has been described forthe case that the valve seated in the connector is a one-way valve, butthe present invention can also be applied to connectors seating othertypes of valves.

[0042] Moreover, the structure of the connector portion provided at thefirst connector member 1 or the second connector member 2 is not limitedto the male thread 5, the female thread 6 or tapered end portion asdescribed above. That is to say, the present invention can beeffectively applied to any structure in which coupling and decoupling anengagement is carried out by rotating relatively to one another.

INDUSTRIAL APPLICABILITY

[0043] A connector with valve according to the present invention can beassembled easily, makes it possible to reassemble the line, and, byabsorbing twisting of the line, to reduce the possibility of looseningor dislodging and to reduce the load due to rotational torque acting onthe tube or the connected object.

1. A rotary connector with valve, comprising a first and a secondconnector member each having a fitting portion and a connector portionprovided with an inner bore serving as a liquid flow path, and a valvemember arranged in the liquid flow path, wherein the first and thesecond connector member are coupled rotatably to one another by fittingthe fitting portions together, wherein the valve member is seated in avalve-seating portion formed in the fitting portion; wherein the fittingportions of the first and the second connector members are provided withrespective valve-pressing portions facing the valve-seating portion,wherein, by clamping and pressing at least a portion of the valve memberbetween the two valve-pressing portions, liquid-tightness is preservedbetween the inner bore and the outside of the connector at a location atwhich the two fitting portions are coupled; and wherein a pressing forcewith which the two valve-pressing portions act on the valve member isset such that a frictional force exerted between the two valve-pressingportions and the valve member is in a range that allows the firstconnector member and the second connector member to rotate relatively toone another.
 2. The rotary connector with valve according to claim 1,wherein at least one of the connector portions of the first and secondconnector members has a structure with which objects to be connected canbe engaged by mutual rotation, wherein the pressing force acting on thevalve member is set such that the torque for rotating the firstconnector member and the second connector member relatively to oneanother against the frictional force exerted between the twovalve-pressing portions and the valve member is smaller than the torquenecessary to dislodge the engagement of the objects to be connected andthe connector portion.
 3. The rotary connector with valve according toclaim 1, wherein the valve member has a base portion that issubstantially cylindrical and inside of which a valve is formed, and aflange formed at one end thereof, wherein the valve-seating portion isformed in one of the fitting portions, and has a substantially circularcavity that is coaxial with the inner bore and a large diameter portionthat is provided at an aperture end of the cavity, and wherein an endface that is formed by a step between the large diameter portion and thecavity and that is perpendicular to the inner bore acts as one of thevalve-pressing portions; wherein an end face of the fitting portion thatis not provided with the valve-seating portion acts as the othervalve-pressing portion; and wherein the flange is clamped and pressedbetween the two valve-pressing portions.
 4. The rotary connector withvalve according to claim 3, wherein the fitting portion that is notprovided with the valve-seating portion has a valve-holding portion thatprotrudes in axial direction towards the valve-seating portion on aninner peripheral side of the end face forming the valve-pressingportion, and wherein protrusion of the valve member toward the innerbore is prevented by the valve-holding portion.
 5. The rotary connectorwith valve according to claim 1, wherein the valve member has a baseportion that is substantially cylindrical and inside of which a valve isformed; wherein the valve-seating portion is formed in one fittingportion, and has a substantially circular cavity that is coaxial withthe inner bore, an inner peripheral surface at an end portion thereofacting as a valve-pressing portion; wherein the fitting portion that isnot provided with the valve-seating portion has a cylindrical protrusionportion that is linked to the inner bore, an outer peripheral surface ofthe cylindrical protrusion acting as a valve-pressing portion; andwherein a cylindrical end portion of the base portion of the valvemember is clamped and pressed between the two valve-pressing portions.6. The rotary connector with valve according to claim 1 or 5, whereinboth the two valve-pressing portions have a ring-shaped rib, and thering-shaped ribs are arranged in opposition to one another, such thatthey abut against the valve member.
 7. The rotary connector with valveaccording to claim 6, wherein dimensions of the ribs are set such thatan amount of the valve member deformed by pressure is in a range of 10to 70% of the valve member's wall thickness.
 8. The rotary connectorwith valve according to claim 7, wherein the range is 30 to 60%.
 9. Therotary connector with valve according to claim 1, wherein the valvemember seated in the valve-seating portion is a one-way valve member.